From cd8b89280c1c843756a2c95ed50a1a6446b42b52 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Fri, 4 May 2018 14:49:55 -0700 Subject: bpf: btf: Tests for BPF_OBJ_GET_INFO_BY_FD and BPF_BTF_GET_FD_BY_ID This patch adds test for BPF_BTF_GET_FD_BY_ID and the new btf_id/btf_key_id/btf_value_id in the "struct bpf_map_info". It also modifies the existing BPF_OBJ_GET_INFO_BY_FD test to reflect the new "struct bpf_btf_info". Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov Acked-by: Song Liu Signed-off-by: Daniel Borkmann --- tools/testing/selftests/bpf/test_btf.c | 289 +++++++++++++++++++++++++++++++-- 1 file changed, 276 insertions(+), 13 deletions(-) (limited to 'tools/testing/selftests/bpf/test_btf.c') diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c index b7880a20fad1..c8bceae7ec02 100644 --- a/tools/testing/selftests/bpf/test_btf.c +++ b/tools/testing/selftests/bpf/test_btf.c @@ -1047,9 +1047,13 @@ struct btf_get_info_test { const char *str_sec; __u32 raw_types[MAX_NR_RAW_TYPES]; __u32 str_sec_size; - int info_size_delta; + int btf_size_delta; + int (*special_test)(unsigned int test_num); }; +static int test_big_btf_info(unsigned int test_num); +static int test_btf_id(unsigned int test_num); + const struct btf_get_info_test get_info_tests[] = { { .descr = "== raw_btf_size+1", @@ -1060,7 +1064,7 @@ const struct btf_get_info_test get_info_tests[] = { }, .str_sec = "", .str_sec_size = sizeof(""), - .info_size_delta = 1, + .btf_size_delta = 1, }, { .descr = "== raw_btf_size-3", @@ -1071,20 +1075,274 @@ const struct btf_get_info_test get_info_tests[] = { }, .str_sec = "", .str_sec_size = sizeof(""), - .info_size_delta = -3, + .btf_size_delta = -3, +}, +{ + .descr = "Large bpf_btf_info", + .raw_types = { + /* int */ /* [1] */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), + BTF_END_RAW, + }, + .str_sec = "", + .str_sec_size = sizeof(""), + .special_test = test_big_btf_info, +}, +{ + .descr = "BTF ID", + .raw_types = { + /* int */ /* [1] */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), + /* unsigned int */ /* [2] */ + BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), + BTF_END_RAW, + }, + .str_sec = "", + .str_sec_size = sizeof(""), + .special_test = test_btf_id, }, }; +static inline __u64 ptr_to_u64(const void *ptr) +{ + return (__u64)(unsigned long)ptr; +} + +static int test_big_btf_info(unsigned int test_num) +{ + const struct btf_get_info_test *test = &get_info_tests[test_num - 1]; + uint8_t *raw_btf = NULL, *user_btf = NULL; + unsigned int raw_btf_size; + struct { + struct bpf_btf_info info; + uint64_t garbage; + } info_garbage; + struct bpf_btf_info *info; + int btf_fd = -1, err; + uint32_t info_len; + + raw_btf = btf_raw_create(&hdr_tmpl, + test->raw_types, + test->str_sec, + test->str_sec_size, + &raw_btf_size); + + if (!raw_btf) + return -1; + + *btf_log_buf = '\0'; + + user_btf = malloc(raw_btf_size); + if (CHECK(!user_btf, "!user_btf")) { + err = -1; + goto done; + } + + btf_fd = bpf_load_btf(raw_btf, raw_btf_size, + btf_log_buf, BTF_LOG_BUF_SIZE, + args.always_log); + if (CHECK(btf_fd == -1, "errno:%d", errno)) { + err = -1; + goto done; + } + + /* + * GET_INFO should error out if the userspace info + * has non zero tailing bytes. + */ + info = &info_garbage.info; + memset(info, 0, sizeof(*info)); + info_garbage.garbage = 0xdeadbeef; + info_len = sizeof(info_garbage); + info->btf = ptr_to_u64(user_btf); + info->btf_size = raw_btf_size; + + err = bpf_obj_get_info_by_fd(btf_fd, info, &info_len); + if (CHECK(!err, "!err")) { + err = -1; + goto done; + } + + /* + * GET_INFO should succeed even info_len is larger than + * the kernel supported as long as tailing bytes are zero. + * The kernel supported info len should also be returned + * to userspace. + */ + info_garbage.garbage = 0; + err = bpf_obj_get_info_by_fd(btf_fd, info, &info_len); + if (CHECK(err || info_len != sizeof(*info), + "err:%d errno:%d info_len:%u sizeof(*info):%lu", + err, errno, info_len, sizeof(*info))) { + err = -1; + goto done; + } + + fprintf(stderr, "OK"); + +done: + if (*btf_log_buf && (err || args.always_log)) + fprintf(stderr, "\n%s", btf_log_buf); + + free(raw_btf); + free(user_btf); + + if (btf_fd != -1) + close(btf_fd); + + return err; +} + +static int test_btf_id(unsigned int test_num) +{ + const struct btf_get_info_test *test = &get_info_tests[test_num - 1]; + struct bpf_create_map_attr create_attr = {}; + uint8_t *raw_btf = NULL, *user_btf[2] = {}; + int btf_fd[2] = {-1, -1}, map_fd = -1; + struct bpf_map_info map_info = {}; + struct bpf_btf_info info[2] = {}; + unsigned int raw_btf_size; + uint32_t info_len; + int err, i, ret; + + raw_btf = btf_raw_create(&hdr_tmpl, + test->raw_types, + test->str_sec, + test->str_sec_size, + &raw_btf_size); + + if (!raw_btf) + return -1; + + *btf_log_buf = '\0'; + + for (i = 0; i < 2; i++) { + user_btf[i] = malloc(raw_btf_size); + if (CHECK(!user_btf[i], "!user_btf[%d]", i)) { + err = -1; + goto done; + } + info[i].btf = ptr_to_u64(user_btf[i]); + info[i].btf_size = raw_btf_size; + } + + btf_fd[0] = bpf_load_btf(raw_btf, raw_btf_size, + btf_log_buf, BTF_LOG_BUF_SIZE, + args.always_log); + if (CHECK(btf_fd[0] == -1, "errno:%d", errno)) { + err = -1; + goto done; + } + + /* Test BPF_OBJ_GET_INFO_BY_ID on btf_id */ + info_len = sizeof(info[0]); + err = bpf_obj_get_info_by_fd(btf_fd[0], &info[0], &info_len); + if (CHECK(err, "errno:%d", errno)) { + err = -1; + goto done; + } + + btf_fd[1] = bpf_btf_get_fd_by_id(info[0].id); + if (CHECK(btf_fd[1] == -1, "errno:%d", errno)) { + err = -1; + goto done; + } + + ret = 0; + err = bpf_obj_get_info_by_fd(btf_fd[1], &info[1], &info_len); + if (CHECK(err || info[0].id != info[1].id || + info[0].btf_size != info[1].btf_size || + (ret = memcmp(user_btf[0], user_btf[1], info[0].btf_size)), + "err:%d errno:%d id0:%u id1:%u btf_size0:%u btf_size1:%u memcmp:%d", + err, errno, info[0].id, info[1].id, + info[0].btf_size, info[1].btf_size, ret)) { + err = -1; + goto done; + } + + /* Test btf members in struct bpf_map_info */ + create_attr.name = "test_btf_id"; + create_attr.map_type = BPF_MAP_TYPE_ARRAY; + create_attr.key_size = sizeof(int); + create_attr.value_size = sizeof(unsigned int); + create_attr.max_entries = 4; + create_attr.btf_fd = btf_fd[0]; + create_attr.btf_key_id = 1; + create_attr.btf_value_id = 2; + + map_fd = bpf_create_map_xattr(&create_attr); + if (CHECK(map_fd == -1, "errno:%d", errno)) { + err = -1; + goto done; + } + + info_len = sizeof(map_info); + err = bpf_obj_get_info_by_fd(map_fd, &map_info, &info_len); + if (CHECK(err || map_info.btf_id != info[0].id || + map_info.btf_key_id != 1 || map_info.btf_value_id != 2, + "err:%d errno:%d info.id:%u btf_id:%u btf_key_id:%u btf_value_id:%u", + err, errno, info[0].id, map_info.btf_id, map_info.btf_key_id, + map_info.btf_value_id)) { + err = -1; + goto done; + } + + for (i = 0; i < 2; i++) { + close(btf_fd[i]); + btf_fd[i] = -1; + } + + /* Test BTF ID is removed from the kernel */ + btf_fd[0] = bpf_btf_get_fd_by_id(map_info.btf_id); + if (CHECK(btf_fd[0] == -1, "errno:%d", errno)) { + err = -1; + goto done; + } + close(btf_fd[0]); + btf_fd[0] = -1; + + /* The map holds the last ref to BTF and its btf_id */ + close(map_fd); + map_fd = -1; + btf_fd[0] = bpf_btf_get_fd_by_id(map_info.btf_id); + if (CHECK(btf_fd[0] != -1, "BTF lingers")) { + err = -1; + goto done; + } + + fprintf(stderr, "OK"); + +done: + if (*btf_log_buf && (err || args.always_log)) + fprintf(stderr, "\n%s", btf_log_buf); + + free(raw_btf); + if (map_fd != -1) + close(map_fd); + for (i = 0; i < 2; i++) { + free(user_btf[i]); + if (btf_fd[i] != -1) + close(btf_fd[i]); + } + + return err; +} + static int do_test_get_info(unsigned int test_num) { const struct btf_get_info_test *test = &get_info_tests[test_num - 1]; unsigned int raw_btf_size, user_btf_size, expected_nbytes; uint8_t *raw_btf = NULL, *user_btf = NULL; - int btf_fd = -1, err; + struct bpf_btf_info info = {}; + int btf_fd = -1, err, ret; + uint32_t info_len; - fprintf(stderr, "BTF GET_INFO_BY_ID test[%u] (%s): ", + fprintf(stderr, "BTF GET_INFO test[%u] (%s): ", test_num, test->descr); + if (test->special_test) + return test->special_test(test_num); + raw_btf = btf_raw_create(&hdr_tmpl, test->raw_types, test->str_sec, @@ -1110,19 +1368,24 @@ static int do_test_get_info(unsigned int test_num) goto done; } - user_btf_size = (int)raw_btf_size + test->info_size_delta; + user_btf_size = (int)raw_btf_size + test->btf_size_delta; expected_nbytes = min(raw_btf_size, user_btf_size); if (raw_btf_size > expected_nbytes) memset(user_btf + expected_nbytes, 0xff, raw_btf_size - expected_nbytes); - err = bpf_obj_get_info_by_fd(btf_fd, user_btf, &user_btf_size); - if (CHECK(err || user_btf_size != raw_btf_size || - memcmp(raw_btf, user_btf, expected_nbytes), - "err:%d(errno:%d) raw_btf_size:%u user_btf_size:%u expected_nbytes:%u memcmp:%d", - err, errno, - raw_btf_size, user_btf_size, expected_nbytes, - memcmp(raw_btf, user_btf, expected_nbytes))) { + info_len = sizeof(info); + info.btf = ptr_to_u64(user_btf); + info.btf_size = user_btf_size; + + ret = 0; + err = bpf_obj_get_info_by_fd(btf_fd, &info, &info_len); + if (CHECK(err || !info.id || info_len != sizeof(info) || + info.btf_size != raw_btf_size || + (ret = memcmp(raw_btf, user_btf, expected_nbytes)), + "err:%d errno:%d info.id:%u info_len:%u sizeof(info):%lu raw_btf_size:%u info.btf_size:%u expected_nbytes:%u memcmp:%d", + err, errno, info.id, info_len, sizeof(info), + raw_btf_size, info.btf_size, expected_nbytes, ret)) { err = -1; goto done; } -- cgit v1.2.3-59-g8ed1b